PROJECT SUMMARY Partial support is being requested for three International Symposia on Recent Advances in Otitis Media. The worldwide prevalence of otitis media (OM) and alarming increase in antibiotic resistant bacteria that cause OM make this a serious public health problem. Thus, there is a pressing need for better ways to diagnose, treat and ultimately, prevent OM. To do so however requires a complete understanding of all aspects of this pediatric disease, a stated goal of both Healthy People 2020 (Hearing and Other Sensory or Communication Disorders, ENT-VSL-2: ?Reduce otitis media in children and adolescents?), and the NIDCD strategic plan FY 2017-2021, wherein Priority Area 2 ? Understanding Diseases and Disorders, declares a mandate to improve our understanding of the susceptibility and pathogenesis of OM as related to genetics, prior upper respiratory tract infection, Eustachian tube dysfunction and reflux, bacterial biofilms and microbiome, polymicrobial infections, dysregulation of innate immunity, inflammation and mucus production, mucosal hyperplasia and dysregulation of the resolution of inflammation and tissue repair. Defining the immune pathways for effective middle ear protection by vaccines and identification of new therapeutic targets as well as development of animal models of acute and chronic OM, determination of the impact of vaccination on disease prevalence and infection by other microbes are also cited as major goals within this priority research area. The objectives of the International Symposia on Recent Advances in Otitis Media are fully and uniquely aligned with these strategic goals. We strongly believe that the speed of scientific discovery requires regular broad and in-depth review of the research progress in OM every two years. Importantly, an additional opportunity to define and formulate recommendations for future research directions and funding every four years by the convening of an integrated Research Conference within the Symposium (occurs during U.S.-convened symposia) is also of great value to our collective efforts to identify and promote new and innovative research opportunities. Thereby, with permission and recommendation from NIDCD staff, herein we request support that will span a period of 5 years, during which we will convene the 20th , 21st and 22nd International Symposia on Recent Advances in Otitis Media (in 2019, 2021 and 2023, respectively). The 20th Symposium will be convened June 9-13 in Los Angeles, California; the 21st Symposium will be convened June 6-10 in Tel Aviv, Israel; and the 22nd Symposium will be convened at a U.S. destination that will be decided at the 20th Symposium. These Symposia are expected to foster improved communication amongst diverse research disciplines in the OM research field and help close gaps in our collective knowledge and understanding of the pathogenesis as well as the diagnosis, treatment and/or potential for immunological resolution of OM. This Symposium has also consistently attracted young investigators from many disciplines and from around the world, thus ensuring a future generation of both basic science and clinician investigators who will continue to move the field forward.